' C 549 ] 
than this which fell the 1 2 of July in the evening, and 
wherein my apparatus was as wet as it could be. 
3. It is again certain, by Mr. Ludolf’s third expe- 
riment, mention'd hereafter, that this ceffation does 
cot happen, becaufe the matter of the thunder is ex- 
tindt. u When the rain was abundant (fays he) we 
u remark’d nothing of this force of electricity, altho’ 
<{ the lightning and the claps of thunder were ex- 
" ceeding ftrong.” 
The true caufe of thefe kind of diminutions may 
therefore depend on fome other principles, which 
we have not as yet come to the knowledge of. Hi- 
therto this phenomenon prefents us with a great ma- 
ny variations. I have feen circumftances, wherein 
fimple clouds, without thunder or lightning, pro- 
duced more eledtricity than when there was loud 
thunder : I have feen others, wherein the eledtricity 
did not fhew itfelf but where there was lightning ; 
and, in ihort, others, when the eledtricity, which 
feem’d difhpated during the rain, began again as foon 
as the rain ceafed, altho’ the thunder was very di- 
ftant. The few experiments, hitherto made, are not 
fufficient to pronounce any certain opinion upon, with 
fo many variations. 
The little fuccefs I have had in trying, whether 
ftrong explofions, or violent fermentations of falts, 
fulphurs, and feveral liquors, would not produce 
fome figns of eledtricity, does not furprize me. The 
matter contained in clouds may be of a different na- 
ture. The atmofphere of the earth is a more pow- 
erful fublimator than thofe of our chemifts ; and our 
weak operations will never perfedtly come up to 
thofe of nature. 
It 
